hifi engine

Denon PMA 925R

I have a Denon amp that is used in a public work place and someone decide to place a cup of water on top. Guess what happened next, the not me person, bumped the amp, cup turns over and sparks begin to fly.

Trouble shooting begins. The fuse was blown so I replaced that only to have it blow again. Just hoping it was that simple, yes I waited a about 7 days to ensure it was dry.

After cleaning all the dust out I found two blown caps C501 and C502. The issue I have now is finding the correct part(s). Does any one know where I can order parts from. I have tried Mouser but no luck.

Part infomation: Denon Part number (I think) 256 1034 979, Part name Metalized 0.1uF/50V Remarks CF93A1H104J.

Thank for the help.


Re: Denon PMA 925R

Any mylar .1uf 50 volt (or higher voltage) will work; they are not critical. And Mouser should be able to help you; ask for their technical support desk. I think you will find that there are other problems with that amplifier; spilling water in it will usually not make a capacitor go bad, but it will destroy semiconductors.

Re: Denon PMA 925R

You were correct. I finally got around to replacing the Caps and the fuse still blows. I have noticed that L301 and L302 have black scorch marks on the under side. These sit close to two post which I think are the audio inputs. I am thinking these inductors are shorted in the windings.

The manual only states "inductor 1mH". I hope they are as cheap as the caps Italy.

After looking for the part they are asking for a variety of things that are not listed on the parts list.

Amps/DC voltage/DCR any help on what I am actually looking for would be very helpful again.


Re: Denon PMA 925R

I think the scorched inductors are only a result of the damage, not the cause. Unfortunately, it is impossible to say what damage could have been caused by water in an amplifier as I don't know where the water went. You will need to go through and systematically test each semiconductor for shorts or opens.